28089869 has 2 divisors, whose sum is σ = 28089870. Its totient is φ = 28089868.

The previous prime is 28089863. The next prime is 28089881. The reversal of 28089869 is 96898082.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 27772900 + 316969 = 5270^2 + 563^2 .

It is a cyclic number.

It is not a de Polignac number, because 28089869 - 2⁸ = 28089613 is a prime.

It is a super-2 number, since 2×28089869² = 1578081480874322, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28089863) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14044934 + 14044935.

It is an arithmetic number, because the mean of its divisors is an integer number (14044935).

Almost surely, 2^28089869 is an apocalyptic number.

It is an amenable number.

28089869 is a deficient number, since it is larger than the sum of its proper divisors (1).

28089869 is an equidigital number, since it uses as much as digits as its factorization.

28089869 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 497664, while the sum is 50.

The square root of 28089869 is about 5299.9876414950. The cubic root of 28089869 is about 303.9834254872.

The spelling of 28089869 in words is "twenty-eight million, eighty-nine thousand, eight hundred sixty-nine".